Audio Cutter & Merger
Trim audio, keep or remove ranges, fade in/out, or join up to 10 clips with crossfades.
Try an example: Cut 0.1–0.4 s with a short fade out · Merge two tones with a 0.1 s crossfade
How it works
Cuts an audio file to a start and end time, keeps or removes a list of time ranges, and adds fade-in/fade-out. In merge mode it joins up to 10 clips in order, optionally with a crossfade between them. Output as MP3, M4A, Ogg, Opus, FLAC or WAV.
- Times are parsed strictly (seconds, mm:ss or hh:mm:ss.mmm); only the resulting numbers are written into the ffmpeg filtergraph, never your text.
- Cut mode: ranges to keep are sorted, clipped to the file length and merged where they overlap; "remove" ranges are inverted into the parts to keep. Each part is cut sample-accurately with atrim and the parts are joined with the concat filter.
- Merge mode: every clip is converted to a common sample rate (the highest of the clips, max 48 kHz) and channel layout (stereo if any clip is stereo), then joined with concat, or chained with acrossfade (triangular curves) when a crossfade is set. Each crossfade shortens the total by its length.
- Fade in/out (afade) is applied to the final result. The result is encoded once in the chosen format.
Sources
- FFmpeg filters: atrim, concat, acrossfade, afade (FFmpeg project)
For scripts and AI agents
- JSON API:
POST https://audiocuttermerger.usefulweb.site/api/v1/calculate(same calculation as this page) - Interface description: OpenAPI 3.1 · AI guide: llms.txt
- MCP server (Streamable HTTP):
https://audiocuttermerger.usefulweb.site/mcp· tool nameaudio_cutter_merger
Example request
curl -s -X POST https://audiocuttermerger.usefulweb.site/api/v1/calculate \
-H 'content-type: application/json' \
-d '{…see OpenAPI examples…}'Related tools
- Universal Audio Converter – Convert MP3, WAV, FLAC, Ogg, Opus, M4A and AIFF with bitrate and sample-rate control.
- Audio Loudness Normalizer – Measure LUFS and true peak, then normalise to Spotify, podcast or EBU R 128 targets.